Hereditary thrombophilia (genetic predisposition to thrombosis) is a group of diseases characterised by a tendency to suffer from thrombotic episodes.
A thrombotic, venous or arterial event occurs when the blood (even in small quantities) coagulates inside a blood vessel, adheres to its wall and obstructs it partially or completely, preventing the flow of blood.
The clot is called a thrombus.
In most cases, these are defects or alterations in one or more factors of blood clotting.
Coagulation is a very complex process that involves the intervention in succession of many different factors (proteins). It’s a cascade event, like a chain reaction.
Thrombosis susceptibility genes are gene variants (point mutations to a single nucleotide) that are so frequent in the population that they are considered polymorphic variants. The genes considered are those related to Leiden’s factor V, coagulation factor II (prothrombin) and the MTHFR gene (methylenetetrahydrofolate reductase).
Other genes have been associated with thrombotic states, including: Factor XIII, Beta Fibrinogen, PAI-1, HPA, HFE, APO E, ACE, AGT.
The study of gene variants of these three genes is advisable in:
- Subjects with previous episodes of venous thromboembolism or arterial thrombosis
- Women who intend to take oral contraceptives
- Women with previous episodes of thrombosis in pregnancy
- Women who have had multiple miscarriages
- Women with a previous child with DTN (neural tube defect)
- Pregnant women with IUGR, thrombophlebitis or placental thrombosis
- Those suffering from diabetes.
It is advisable for those who have to undergo any type of surgery (especially those at high thromboembolic risk) to perform an assessment of this risk (first with an examination and an ecocolordoppler and if necessary genetic analysis of saliva) to be able to recommend the best prophylaxis, customised to each individual patient.